These heavy duty sandpaper disc works with a variety of woodworking, paint and dust removal applications. Made out of aluminum oxide, their 40 grit abrasive helps them deliver high precision and pristine sanding/polishing results on materials such as wood, painted surfaces and metal. The aluminum oxide also features premium quality abrasion resistance, anti-static and anti-clogging, ideal for grinding and finishing on plastics, stone, glass and other materials. They are professionally designed provide consistent and even sanding patterns, and work effectively towards smoother surface finishes and overall polishing efforts. Each 5-inch disc features 8 pre-punched holes for efficient chip and dust extraction, while the hook and loop backing prevents any accidental disconnection from the sander, and allows for a quick and easy installation or removal. They possess an open-coated grain that prevents inefficient dust buildup and it is resin bonded for optimal heat resistance.